// ************************************************************************** //
//
//  BornAgain: simulate and fit scattering at grazing incidence
//
//! @file      Core/Basics/MathConstants.h
//! @brief     Defines M_PI and some more mathematical constants.
//!
//! @homepage  http://www.bornagainproject.org
//! @license   GNU General Public License v3 or higher (see COPYING)
//! @copyright Forschungszentrum Jülich GmbH 2018
//! @authors   Scientific Computing Group at MLZ (see CITATION, AUTHORS)
//
// ************************************************************************** //

#ifndef MATHCONSTANTS_H
#define MATHCONSTANTS_H

// undefine macros that may or may not be defined, depending on compiler settings
#undef M_E
#undef M_LOG2E
#undef M_LOG10E
#undef M_LN2
#undef M_LN10
#undef M_PI
#undef M_PI_2
#undef M_PI_4
#undef M_1_PI
#undef M_2_PI
#undef M_2_SQRTPI
#undef M_SQRT2
#undef M_SQRT1_2

// and define them using these potentially inactivated lines from math.h
#define M_E 2.7182818284590452354         /* e */
#define M_LOG2E 1.4426950408889634074     /* log_2 e */
#define M_LOG10E 0.43429448190325182765   /* log_10 e */
#define M_LN2 0.69314718055994530942      /* log_e 2 */
#define M_LN10 2.30258509299404568402     /* log_e 10 */
#define M_PI 3.14159265358979323846       /* pi */
#define M_PI_2 1.57079632679489661923     /* pi/2 */
#define M_PI_4 0.78539816339744830962     /* pi/4 */
#define M_1_PI 0.31830988618379067154     /* 1/pi */
#define M_2_PI 0.63661977236758134308     /* 2/pi */
#define M_2_SQRTPI 1.12837916709551257390 /* 2/sqrt(pi) */
#define M_SQRT2 1.41421356237309504880    /* sqrt(2) */
#define M_SQRT1_2 0.70710678118654752440  /* 1/sqrt(2) */

// additionally, we find convenient:
#define M_TWOPI 6.28318530717958647693

#endif // MATHCONSTANTS_H
